The present invention relates to hysteroscopes of the kind having a shaft comprising an optical system which may be passed through an entrance adaptor arranged for sealing a patient's uterus by negative pressure and which is insertable into the uterus through the cervical passage. Hereinafter such hysteroscopes will be referred to as "of the kind described".
For complete visual examination of the uterus, it is known e.g. from German Gebrauchsmuster No. 70 36 446 and German Offenlegungschrift No. 2 902 829, to make use of a hysteroscope which is inserted through the cervical passage, the entrance being sealed off by means of a spring-loaded cone. Since this seal proved to be unsatisfactory, a method was adopted in which said seal is replaced by an entrance adaptor which, after being placed over the entrance, is held fast by application of a negative pressure. The hysteroscope shaft having the optical system is inserted into the uterus through a proximal rubber seal of the adaptor. To this end, it is necessary for the physician to hold the adaptor with one hand and the hysteroscope shaft coupled to the optical system with the other hand, which leads to a very unstable arrangement, so that the push and pull displacements of the hysteroscope shaft can no longer be performed quietly and sensitively without risk of injuring the cervical passage and the womb.
Consequently, it is an object of the invention to provide means of assuring that the hysteroscope may be guided calmly and sensitively forward and back through the cervical passage, into and out of the womb.